Nick Cannon is opening up about the series of health problems he's faced over the last couple of months. The 31-year-old has revealed that the kidney disease he was hospitalized for earlier this year was a result of an autoimmune disease, People magazine reported…Lupus in particular is when the immune system attacks the body's tissues and organs, according to the Mayo Clinic, and is most known for the butterfly-wing-like rash that appears on the face. Symptoms of lupus are different from case to case, but common symptoms include fever, fatigue, joint pain, the facial rash, chest pain, headaches, dry eyes and skin lesions, the Mayo Clinic.